H. [Abelmoschus] esculentus — Okro (Fe. Gombo). — Exogen ; herbaceous annual ; 2-10 ft. A native of the W. Indies, notably Cuba, where it grows freely in almost all soils ; indigenous also to Africa, wild and abundant on the White Nile, and near the Victoria Nyanza ; long naturalized in India, and commonly cultivated in gardens. The plant is grown in India, for its edible pods, chiefly in Jessore, Rungpore, Bogra, Hooghly, the 24-Pergunnahs, Nuddea, Moorshedabad, and Cuttack ; the culture might be much extended in Bancoorah, Beerbhoom, and Nowgong. It is very common in Burmah; and is being introduced into Algeria.
The fibre is long and silky, and generally strong and pliant ; its breaking strain, according to Roxburgh, is 79 lb. dry, and 95 lb. wet. When well prepared, as in the Southern Presidency, it is adapted for the manufacture of rope, twine, seeking, and paper. In Bengal, its fibre is reputed harsh and brittle, owing doubtless to improper treatment, and it is but little manufactured there. In Dacca and Mymensing, it is used to adulterate jute. It resembles hemp, and, under this name, is exported, to the amount of a few thousand cwt. yearly. In France, the manufacture of paper from this fibre is the subject of a patent ; the fibre receives only mechanical treatment, and affords a paper, called banda, equal to that from pure rage.
H. abelmoschus [A. moschates), grows in Bengal, Travancore, Coromandel, and Burmah. Produces a strong fibre. Plants, cut in flower and immediately steeped, broke at 107 lb. wet and dry. H. furcatus is found in the S. Provinces of India, and in the interior of Bengal. The bark yields an abundance of strong white fibres ; a line broke at 89 lb. dry, and 92 lb. wet. The stems are cut when the plant is flowering, and steeped at once. H. Leckigii, native of S. Africa, is a tall and shrubby species, yielding fibre of great strength and toughness. H. *lances, native of Bengal, with a straight stem 6-14 ft. high, and very smooth bark, thrives luxuriantly with little or no care, yet is very little cultivated for its fibre. The seed is sown in beds in May, and when the plants are 6 in. high, they are set out in rows, 9 in. apart each way. The luxuriant growth and habits of the plant commend it to serious attention. The bark abounds in flaxen fibres, long, glossy, white, fine, and strong, and easy of extraction. H. is a native of Tropical Asia and Africa, common in Indian gardens, abundant in the W. Indies, and selected for culture in the
warmest parts of Victoria. The plant is cut while in flower, and a fine, silky fibre is extracted from the stem, by retting in fresh water. The staple is long and uniform, and said to be adapted to cordage. The tow yielded by it is valuable for paper-making. H. tiliaceus, native of India, Tropical Australia, and the Pacific groups, is extensively used by the natives for making fishing nets, cordage, &c. H. vitifolius, common all over India, is a wild plant yielding a very white, flue and strong fibre, extracted by retting. H. elates, the "Cuba bast" of the W. Indies, is employed in making cigarette wrappers. There are probably several other fibre-yielding species of Hibiscus awaiting research and utilization.
Holoptelea integrifolia—Wawla bast.—Exogen. Native of the W. Indies. The fibre is not strong.
Holostemma Rheedianum.—Exogen. Native of India, from the southernmost province to the base of the Himalayas. It yields a fair fibre, said to be in best condition after the rains.
Humulus Lupulus—Hop (FR., Houblon ; GER., Hopfen).—Exogen. Native of the temperate zone of Europe, Asia, and N. America. The bine of this well-known plant contains a quautity of useful fibre-70-75 per cent. of the dry weight—which is generally thrown away. A section of the Nine is shown in Fig. 664: b, lig,nose ; c, cambium ; e, epidermis ; f, bast fibres, coloured blue by test H ; mag., 100. The fibres are very supple. Their dimensions are :—length : max., 0.748 in.; min., in. ; mean, 0.393 in. ; diameter : max., in.; min., in. ; mean, 0.00061 in.
The fibre is well suited for paper making, especially unbleached paper and cardboard. In Sweden, it has long been applied to textile manufactures. It is extracted from the plant by steeping for 24 hours in cold water containing 5 per cent. of sulphuric acid, or for 20 minutes in boiling water with 3 per cent. of the acid. Another plan is to boil for hour in water containing soap or soda, then to wash, and boil in very dilute acetic acid. The fibre is finally washed, dried, and combed, and then resembles flax.
Iris pseudacorus—Yellow water-iris.—Endogen. A common weed in England and Ireland. The leaves yield when dry about 60 per cent. of available fibre for "half-stuff," which makes a fairly good paper.